Re: [PATCH] meson: move pixman detection to meson

[Thomas Huth <thuth@redhat.com>]

On 26/08/2020 09.02, Paolo Bonzini wrote:
> When pixman is not installed (or too old), but virglrenderer is available
> and "configure" has been run with "--disable-system", the build currently
> aborts when trying to compile vhost-user-gpu (since it requires pixman).
> 
> Let's skip the build of vhost-user-gpu when pixman is not installed or
> too old.  Instead of adding CONFIG_PIXMAN, it is simpler to move the
> detection to pixman.
> 
> Based on a patch by Thomas Huth. <thuth@redhat.com>
> 
> Fixes: 9b52b17ba5 ("configure: Allow to build tools without pixman")
> Reported-by: Rafael Kitover <rkitover@gmail.com>
> Reported-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  configure                          | 21 ++-------------------
>  contrib/vhost-user-gpu/meson.build |  3 ++-
>  meson.build                        | 12 +++++++-----
>  3 files changed, 11 insertions(+), 25 deletions(-)
> 
> diff --git a/configure b/configure
> index a5fa472c64..51b6164f69 100755
> --- a/configure
> +++ b/configure
> @@ -3923,20 +3923,6 @@ if test "$modules" = yes; then
>      fi
>  fi
>  
> -##########################################
> -# pixman support probe
> -
> -if test "$softmmu" = "no"; then
> -  pixman_cflags=
> -  pixman_libs=
> -elif $pkg_config --atleast-version=0.21.8 pixman-1 > /dev/null 2>&1; then
> -  pixman_cflags=$($pkg_config --cflags pixman-1)
> -  pixman_libs=$($pkg_config --libs pixman-1)
> -else
> -  error_exit "pixman >= 0.21.8 not present." \
> -      "Please install the pixman devel package."
> -fi

The "else" part now got completely lost, didn't it? pixman is required
for building the softmmu targets, so we should error out if configure is
run with a softmmu target on systems where pixman is not installed.

Maybe you can simply replace the above check with:

if test "$softmmu" = "yes" && ! $pkg_config --atleast-version=0.21.8
pixman-1 > /dev/null 2>&1; then
  error_exit "pixman >= 0.21.8 not present." \
      "Please install the pixman devel package."
fi

?

 Thomas


>  ##########################################
>  # libmpathpersist probe
>  
> @@ -6649,8 +6635,8 @@ echo_version() {
>      fi
>  }
>  
> -# prepend pixman and ftd flags after all config tests are done
> -QEMU_CFLAGS="$pixman_cflags $fdt_cflags $QEMU_CFLAGS"
> +# prepend ftd flags after all config tests are done
> +QEMU_CFLAGS="$fdt_cflags $QEMU_CFLAGS"
>  QEMU_LDFLAGS="$fdt_ldflags $QEMU_LDFLAGS"
>  
>  config_host_mak="config-host.mak"
> @@ -8053,9 +8039,6 @@ fi
>  
>  done # for target in $targets
>  
> -echo "PIXMAN_CFLAGS=$pixman_cflags" >> $config_host_mak
> -echo "PIXMAN_LIBS=$pixman_libs" >> $config_host_mak
> -
>  if [ "$fdt" = "git" ]; then
>    subdirs="$subdirs dtc"
>  fi
> diff --git a/contrib/vhost-user-gpu/meson.build b/contrib/vhost-user-gpu/meson.build
> index 8df4c13bc5..7d9b29da8b 100644
> --- a/contrib/vhost-user-gpu/meson.build
> +++ b/contrib/vhost-user-gpu/meson.build
> @@ -1,5 +1,6 @@
>  if 'CONFIG_TOOLS' in config_host and 'CONFIG_VIRGL' in config_host \
> -    and 'CONFIG_GBM' in config_host and 'CONFIG_LINUX' in config_host
> +    and 'CONFIG_GBM' in config_host and 'CONFIG_LINUX' in config_host \
> +    and pixman.found()
>    executable('vhost-user-gpu', files('vhost-user-gpu.c', 'virgl.c', 'vugbm.c'),
>               link_with: libvhost_user,
>               dependencies: [qemuutil, pixman, gbm, virgl],
> diff --git a/meson.build b/meson.build
> index bcd39b39da..57c2fe2b65 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -114,8 +114,11 @@ if 'CONFIG_GNUTLS' in config_host
>    gnutls = declare_dependency(compile_args: config_host['GNUTLS_CFLAGS'].split(),
>                                link_args: config_host['GNUTLS_LIBS'].split())
>  endif
> -pixman = declare_dependency(compile_args: config_host['PIXMAN_CFLAGS'].split(),
> -                            link_args: config_host['PIXMAN_LIBS'].split())
> +pixman = not_found
> +if have_system or have_tools
> +  pixman = dependency('pixman', required: have_system, version:'>=0.21.8',
> +                      static: enable_static)
> +endif
>  pam = not_found
>  if 'CONFIG_AUTH_PAM' in config_host
>    pam = cc.find_library('pam')
> @@ -1094,9 +1097,7 @@ if have_tools
>    if 'CONFIG_VHOST_USER' in config_host
>      subdir('contrib/libvhost-user')
>      subdir('contrib/vhost-user-blk')
> -    if 'CONFIG_LINUX' in config_host
> -      subdir('contrib/vhost-user-gpu')
> -    endif
> +    subdir('contrib/vhost-user-gpu')
>      subdir('contrib/vhost-user-input')
>      subdir('contrib/vhost-user-scsi')
>    endif
> @@ -1303,6 +1304,7 @@ summary_info += {'SDL image support': sdl_image.found()}
>  # TODO: add back version
>  summary_info += {'GTK support':       config_host.has_key('CONFIG_GTK')}
>  summary_info += {'GTK GL support':    config_host.has_key('CONFIG_GTK_GL')}
> +summary_info += {'pixman':            pixman.found()}
>  # TODO: add back version
>  summary_info += {'VTE support':       config_host.has_key('CONFIG_VTE')}
>  summary_info += {'TLS priority':      config_host['CONFIG_TLS_PRIORITY']}
>